This invention relates to an improved value printing device such as for use in a postage meter or register, and, more particularly, to such a device having improved apparatus for imparting a reciprocal motion to the carriage, housing and inking roller.
Cross reference is hereby made to a copending patent application assigned to the same assignee as this application entitled: "Value Printing Device Warning Function For Replacing An Inking Member" by D. Buan et al, Ser. No. 334,934, filed on Dec. 28, 1981. Cross reference is also made to U.S. Patents assigned to the same assignee as this application. The first is U.S. Pat. No. 4,412,491 entitled: "System For Sensing An Inking Member In A Value Printing Device" by D. Buan et al, and second is U.S. Pat. No. 4,401,031 entitled "Disposable Self-Contained Cartridge For Value Printing Device" by D. Buan. Cross reference is also made to the copending application, assigned to the same assignee as this application, entitled "Inking Apparatus for a Value Printing Device" by D. Buan (U.S. application Ser. No. 593,228, filed on Mar. 27, 1984). These patents and applications are incorporated herein by reference in their entireties.
Value printing devices such as postage meters, labeling apparatus, registers and the like are constructed to print information to a surface such as a mailpiece by contacting the surface with inked print characters. Generally, the print characters are raised against the background of a printing head. In such systems, the inking typically occurs immediately prior to the printing event.
In a postage meter, for example, relative movement occurs between the inking roller and the print characters so that the movement is capable of permitting contact therebetween and, consequently, the inking of the characters. Inking rollers normally contain their own inking supply. While various inventive aspects which follow are described in connection with commercially available postage meters, it will be understood that such aspects apply equally to any printing device with like characteristics.
In rotary head postage meters and registers such as Pitney-Bowes' Models 5300, 6300 and 6500 meters, the print characters are contained on a rotary printing head which revolves relative to a stationery inking roller during the print cycle. When the raised print characters encounter the inking roller, they make contact and, thus, are inked.
In so called flat-bed postage meters, meters, such as a Pitney-Bowes' Model 5700 Series meter, the print characters are contained on a horizontal flat printing head. In the print cycle, the inking roller and its support carriage are moved across the print characters immediately prior to printing. The characters remain stationery during both inking and printing. The mailpiece to be marked, or have postage applied thereto, is raised rapidly against the printhead with enough force to effect the desired marking. After printing and removal of the mailpiece, the inking roller moves back across the printing head to its original rest or home position.
The invention described in this patent application can apply to both rotary and flat-bed postage meters and registers. For the purpose of convenience, the present invention is described specifically with regard to a flat-bed Pitney-Bowes' Model 5700 Series meter which has a well-known configuration and has been available commercially for some time.
Various aspects of this type of pastage meter have been described in prior patents. These include U.S. Pat. Nos. 3,069,084 relating to a registering mechanism, 3,244,096 relating to an imprinting machine with controlled imprinting force, and 3,310,139 relating to a drive system. Also, U.S. Pat. No. 3,143,963 is of note in that it relates to an apparatus for limiting the number of cycles of a postage meter in accordance with the capacity of the inking roller and, thereafter, rendering the inking roller unfit for use in the postage meter.
In existing prior art devices, there has been a tendency for the inking roller to move out of its predetermined alignment during its movement with the carriage while effecting its operational cycle. This problem may be due to improper loading of the inking roller into the housing or the improper placement of the housing into the carriage. It may also be due to an excessive interference fit either between the inking roller and indicia or between the inking roller shaft ends and the end plates of the machine in which it is located. Whatever the cause, it has been found that there is a possibility that the proper seating in the housing of the inking roller and the proper seating of the cartridge can become disturbed during the use of the roller and thereby cause a malfunction or stoppage of the postal meter. This, in turn, can render the postal meter inoperable resulting in excessive down time of the system.
Currently, such as in the example of the Pitney-Bowes' Model 5700 Series meter, an inking roller is replaced when, in the operator's judgment, the impressions produced by the meter grow faint or weak. When this is done, a hand tool especially designed for this purpose is used to grip the ends of the ink roller and remove it from the moveable carriage supporting it in the device. The hand tool is necessary to avoid manual removal of the inking roller. A manual removal could result in inking or staining of the operator's hands or clothing which would be undesirable. Frequently, however, the hand tool is misplaced or difficult to find. Without it, the carriage can only be removed manually with the above described inconvenience.
The prior art devices are improved by the present invention due to the various new and improved parts, constructions, arrangements of elements and the like.